What about blood work? Did you and your regular partner get type specific tests for herpes to know yours/his status? That would be good to find out if this is a recent infection or not.
As for how this has happened, well, it was through sex. lol Maybe you have if for a long time - meaning it's an old infection - but never noticed symptoms; maybe your partner has it, and has recently transmitted to you. The swab will be useful to know what type it is - I or II -, since type I is usually transmitted through oral sex, while the type II is usually through intercourse.
Herpes is often transmitted when no symptoms are visible, so your partner might have given to you even when there's was no visible outbreaks orally or genitally. But before trying to understand what it happened, wait for your swab result (call the office within a couple of days to learn about it) and maybe get blood tests for you and your partner. Post the results here and we'll gladly help you.
I have had a swab done but the results arent back yet? the GP said she thinks its herpes but i havent had anything 100% to prove that yet! I just dont understand how this has happened?
Did they swab the lesion to have it cultured? If they didn't, go back and ask for a swab (culture or PCR). This way you can know what type of herpes you have - it's important to know your prognosis. Visual diagnosis alone is NOT enough.
Also ask for a type specific blood test for you and your partner - IgG, not IgM.
I have been to my GP and unfortunately said I have this condition, i feel absolutely shocked, upset, devestated, i feel like my whole life has flipped! I have been with my partner for 5 years and neither of us have cheated and thankfully my partner is amazing and is supporting me through this difficult time. My GP said i could have had this for many years but it has only just decided to come out :O( I feel so sad about this! I'm scared this is going to control my life!
this can be many things going on. call your doctor tomorrow and make an appointment to be seen again for a proper work up.
grace